Fatliquirs

What fatliquors are

Fatliquors (spelt fatliquirs in this catalogue) are emulsified oils that lubricate collagen after tannage so the leather is soft, strong and pleasant to handle. They may be anionic synthetic oils, sulphited fish oils, vegetable-oil concentrates, weakly cationic pastes or non-ionic handle modifiers. Dyna Glycols manufactures the VENOL liquor and VENSOFT families for chrome, semi-chrome, vegetable and combination tannages, including white and pastel articles that need lightfast fat.

A fatliquor must penetrate, exhaust and stay stable in the electrolytes of the dye-house: acid, salt, hard water and sometimes chrome. Lightfast grades are required for whites and anilines. Garment and gloving need inner softness and run; shoe upper needs a firmer, more filled handle. The catalogue is organised so a tannery can blend a penetrating synthetic (ASN), a vegetable concentrate (K-2), a sulphited fish oil for fluff (SFGM), a weakly anionic paste (WWL) and cationic or non-ionic tops (CWS, SFC).

How Dyna Glycols manufactures fatliquors

Anionic fatliquors are produced as micro-emulsifiable oils with controlled water content, pH of emulsion and ionic character. Concentrates such as VENOL LIQUOR K-2 are supplied at high active content (about 98%) so the tannery or formulator can dilute. Cationic and non-ionic pastes (VENSOFT CWS, SFC) are fatty-acid condensation products finished to a pourable paste.

Lightfast synthetic grades are based on saturated hydrocarbons or related synthetics rather than highly unsaturated fish oil, so they are preferred for white goat and sheep and for aniline. Sulphited fish-oil types remain the tool for fluffy milled garment.

Typical grades in this range

Ionic type and lightfastness decide the first shortlist. Open each product page for emulsion behaviour and suggested % on shaved weight.

• VENOL LIQUOR ASN — lightfast anionic synthetic; micro-emulsion; whites, pastels, aniline
• VENOL LIQUOR K-2 — concentrated vegetable-oil anionic (~98% active)
• VENOL LIQUOR SFGM — sulphited fish oil and synthetics for fluffy garment and milled leather
• VENOL LIQUOR WWL PASTE — weakly anionic paste; electrolyte-stable dispersant and dyeing oil
• VENSOFT CWS — cationic fatty-acid condensation paste; chrome tannage, suede main fat, top fat
• VENSOFT SFC — non-ionic handle modifier; suede, nubuck, full grain; lightfast
• Related types on request: VENSOFT SFC-CONC, VENOL LSO, LS, LSF, SXE

Where fatliquors are used

Shoe upper and softy side: blend a penetrating synthetic (ASN, often 3–6% on shaved weight) with a vegetable concentrate (K-2) to reach the target softness without a greasy surface. Upholstery may take higher ASN (around 8–10% on buffalo).

Garment and gloving: SFGM in stages through retanning for run and inner softness (goat garment often 12–15% on shaved weight; cow and sheep lower). Add SFC in the exhausted dye bath or final wash for elegant handle on suede and nubuck.

White and pastel: ASN plus WWL paste (and titanium dioxide dispersed with WWL where needed). Cationic CWS as a top fat or in chrome tannage for suede. Avoid dark, unsaturated oils if lightfastness is specified.

How to specify fatliquors

State tannage, article (upper, nappa, suede, upholstery, white), required softness, lightfastness, and whether the fat must be stable to chrome or vegetable tannin. Give the current % on shaved weight and the ionic mix in the bath.

If the tannery blends its own fat, request K-2 or another concentrate plus a synthetic emulsifier grade. If they buy ready fatliquor, match the ionic type and water content of the competitor TDS.

Quality, documents and supply

Lots are released against appearance, solids or water, pH of 10% emulsion, and ionic character. SDS and COA follow verification. Emulsion stability in acid, salt and chrome should be checked in the tannery float, not only in distilled water.

Store frost-free. Pastes may need warming and stirring. Typical shelf life is six months in closed containers. Do not contaminate anionic drums with cationic tops.

Practical notes on fatliquors

ASN forms a micro-emulsion and is described as a good emulsifier of fish and vegetable oils in a blend. Use it as the “engine” of a mixed fatliquor when the tannery still wants a natural oil fraction.

K-2 at ~98% active is a formulator’s concentrate. Dilute with water to the cost and softness required, or blend with synthetics. It is not a ready 50% emulsion.

SFGM can be used in rechroming to help chrome exhaustion and later in retanning in instalments. That staged addition is what gives fluffy garment rather than dumping the whole dose at the end.

WWL paste is weakly anionic, electrolyte-stable, and a dye-levelling / pigment-dispersing oil as well as a fat. It is the usual partner for white grain with TiO2.

Cationic CWS and non-ionic SFC are tops and handle modifiers. Adding them into a strongly anionic fat bath without process thought can crash the emulsion. Follow the product page: CWS in chrome or as top; SFC in acidified exhausted dye bath or main fat as directed.

Dyna Glycols can ship a small evaluation kit of ASN, K-2, SFGM, WWL, CWS and SFC so the dye-house can rebuild a fatliquor on the actual article.

Ordering and evaluating fatliquors

Dyna Glycols supports fatliquors with laboratory samples, current SDS, TDS and COA from the Kandla SEZ manufacturing network. Tell us the intended application, the substrate, the required moles or molecular weight, and any limits on colour, odour, cloud point, hydroxyl value, pH or residual feedstock. A matching catalogue grade of fatliquors in the Leather Chemicals family can then be confirmed, or a custom batch can be planned on the ethoxylation, esterification or related plant.

When you evaluate fatliquors, send the competitor grade if one exists, the bath or emulsion conditions, and the tests your receiving laboratory will run. Pack options for fatliquors typically include drums, IBCs and bulk where the viscosity and melting point of the selected grade allow safe handling from the Leather Chemicals manufacturing line.

A first order of fatliquors is easier when the purchase specification lists identity tests, not only a local trade name. Hydroxyl value, saponification value, acid value, cloud point, pH, water, colour and appearance are the numbers the Kandla QA laboratory can lock. If your QC uses a different solvent or a different cloud-point electrolyte for fatliquors, write that method on the order so the COA speaks the same language.

Custom lots of fatliquors are quoted after the hydrophobe or acid/alcohol pair, the target analytical window, the annual volume and the pack. Pilot batches are available when a catalogue point in the Leather Chemicals range is close but not exact. Once a trial lot is approved, that TDS should be frozen so the tenth delivery of fatliquors matches the first approved drum.